export type RawFlagConfig = { pattern: string; colors: string[] };

export const FLAG_PATTERNS = [
  "triband-h",
  "triband-v",
  "diagonal",
  "nordic-cross",
  "cross",
  "canton",
  "triangle",
  "chevron",
  "quartered",
  "bordered",
  "circle",
  "star",
] as const;

export type FlagPattern = (typeof FLAG_PATTERNS)[number];

export interface FlagConfig {
  pattern: FlagPattern;
  colors: string[];
}

export type UserAvatarType = "flag" | "uploaded";
export type TeamAvatarType = "owner" | "flag" | "uploaded";

export type AvatarData =
  | { type: "image"; url: string }
  | { type: "flag"; config: FlagConfig };

const FLAG_PATTERN_SET = new Set<string>(FLAG_PATTERNS);
const HEX_COLOR_RE = /^#[0-9a-fA-F]{6}$/;

export function isFlagPattern(value: unknown): value is FlagPattern {
  return typeof value === "string" && FLAG_PATTERN_SET.has(value);
}

export function isFlagConfig(value: unknown): value is FlagConfig {
  if (!value || typeof value !== "object") return false;
  const config = value as { pattern?: unknown; colors?: unknown };
  return (
    isFlagPattern(config.pattern) &&
    Array.isArray(config.colors) &&
    config.colors.length === 3 &&
    config.colors.every((color) => typeof color === "string" && HEX_COLOR_RE.test(color))
  );
}

export function parseFlagConfig(value: unknown): FlagConfig | null {
  return isFlagConfig(value) ? value : null;
}